// Copyright 2014 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef CONTENT_RENDERER_SCREEN_ORIENTATION_SCREEN_ORIENTATION_DISPATCHER_H_
#define CONTENT_RENDERER_SCREEN_ORIENTATION_SCREEN_ORIENTATION_DISPATCHER_H_

#include <memory>
#include <utility>

#include "base/compiler_specific.h"
#include "base/id_map.h"
#include "base/macros.h"
#include "content/public/renderer/render_frame_observer.h"
#include "device/screen_orientation/public/interfaces/screen_orientation.mojom.h"
#include "third_party/WebKit/public/platform/modules/screen_orientation/WebLockOrientationCallback.h"
#include "third_party/WebKit/public/platform/modules/screen_orientation/WebScreenOrientationClient.h"
#include "third_party/WebKit/public/platform/modules/screen_orientation/WebScreenOrientationLockType.h"
#include "third_party/WebKit/public/platform/modules/screen_orientation/WebScreenOrientationType.h"

namespace content {

using device::mojom::ScreenOrientationAssociatedPtr;
using device::mojom::ScreenOrientationLockResult;

class RenderFrame;

// ScreenOrientationDispatcher implements the WebScreenOrientationClient API
// which handles screen lock. It sends lock (or unlock) requests to the browser
// process and listens for responses and let Blink know about the result of the
// request via WebLockOrientationCallback.
class CONTENT_EXPORT ScreenOrientationDispatcher : public RenderFrameObserver,
                                                   NON_EXPORTED_BASE(public blink::WebScreenOrientationClient) {
public:
    explicit ScreenOrientationDispatcher(RenderFrame* render_frame);
    ~ScreenOrientationDispatcher() override;

private:
    friend class ScreenOrientationDispatcherTest;

    // RenderFrameObserver implementation.
    void OnDestruct() override;

    // blink::WebScreenOrientationClient implementation.
    void lockOrientation(
        blink::WebScreenOrientationLockType orientation,
        std::unique_ptr<blink::WebLockOrientationCallback> callback) override;
    void unlockOrientation() override;

    void OnLockOrientationResult(int request_id,
        ScreenOrientationLockResult result);

    void CancelPendingLocks();

    int GetRequestIdForTests();

    void EnsureScreenOrientationService();

    // This should only be called by ScreenOrientationDispatcherTest
    void SetScreenOrientationForTests(
        ScreenOrientationAssociatedPtr& screen_orientation_for_tests)
    {
        screen_orientation_ = std::move(screen_orientation_for_tests);
    }

    // The pending_callbacks_ map is mostly meant to have a unique ID to associate
    // with every callback going trough the dispatcher. The map will own the
    // pointer in the sense that it will destroy it when Remove() will be called.
    // Furthermore, we only expect to have one callback at a time in this map,
    // which is what IDMap was designed for.
    using CallbackMap = IDMap<std::unique_ptr<blink::WebLockOrientationCallback>>;
    CallbackMap pending_callbacks_;

    ScreenOrientationAssociatedPtr screen_orientation_;

    DISALLOW_COPY_AND_ASSIGN(ScreenOrientationDispatcher);
};

} // namespace content

#endif // CONTENT_RENDERER_SCREEN_ORIENTATION_SCREEN_ORIENTATION_DISPATCHER_H_
